Every dollar of ad spend has a break-even point, and most merchants have never computed theirs. Start with the ROAS calculator to measure what campaigns return today, then use the break-even ROAS calculator to find the return your margin actually requires. A 4x ROAS sounds strong until you learn that a 25%-margin product needs exactly 4x just to break even on the ad.
Amazon sellers work the same math upside down: ACOS is ad spend as a share of ad revenue, and TACOS spreads that spend across total sales to show whether ads are building organic momentum or just buying every order. Either view has to agree with your margin sheet, and finding out inside a calculator is cheaper than finding out in the bank account.
The click-level tools connect the funnel: CPC and CTR set what a visitor costs, conversion rate turns that into a cost per order, and the ad budget calculator scales the whole chain to a monthly number. Change one input and every downstream metric moves, which is exactly how a paid channel should be planned before the money is spent.
Frequently asked questions
What is a good ROAS for e-commerce ads?
It depends entirely on gross margin. A store with 70% margins breaks even near 1.4x, while a 25%-margin store needs 4x just to avoid losing money. As a working benchmark, most profitable DTC campaigns land between 3x and 5x, with 4x a common target. Compute your own break-even ROAS from margin first; a benchmark that ignores your margin is noise.
What is the difference between ROAS and ACOS?
They are the same measurement inverted. ROAS divides ad revenue by ad spend, so higher is better; ACOS divides spend by revenue, so lower is better. A 4x ROAS equals a 25% ACOS. Amazon reports ACOS while most other platforms report ROAS, so sellers running both usually convert one into the other to compare campaigns on a single scale.
How much should I spend on advertising as a percentage of revenue?
Established e-commerce stores typically spend 7–12% of revenue on advertising; growth-stage brands push 15–25% and accept thin or negative first-order profit to acquire customers. The honest ceiling is set by contribution margin: if ads plus product cost plus fulfillment exceed the order value and repeat purchases do not close the gap, the budget is too big at any percentage.
How do I know if a paid campaign is actually profitable?
Check profit per order, not platform-reported ROAS. Take average order value, subtract product cost, fees, shipping, and cost per acquisition; if the remainder is positive, the campaign makes money on the first order. Many campaigns are first-order break-even by design and rely on repeat purchases, which is fine only if you have measured your repeat rate rather than hoped for it.
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